Although Garcia turned in his best start in several weeks, his opposite on the mound, left-hander Jason Vargas, proved to be slightly more effective and the Cardinals succumbed in the series finale, 2-1.
The Redbirds are now 0-for-5 when given a chance to sweep an opponent at the tail end of a three-game series.
St. Louis managed six hits, never reached a base on balls and went down swinging six times.
"I give credit to Vargas, I am not sure why, but we were under the ball," Cardinals manager Tony La Russa said. "If you are under the ball, that is tough to be productive. If we stay under the ball, we will be not productive the next time we play. For whatever reason. That is where you have to leave it."
Albert Pujols accounted for the Cardinals lone run, but it came with more difficulty than he hoped.
The first baseman took a ball deep to left-center field in the bottom of the fourth and started down the line with his typical home run trot. The ball hung up a bit high, however, and Mariners left fielder Milton Bradley made a play at the wall to bring the ball back in play. The umpire ruled it in the park, bringing about only the second use of Busch Stadium's replay system.
After conferring around the video, the ump crew ruled correctly that Bradley indeed robbed Pujols of his 16th home run.
The point proved moot when Pujols advanced on a wild pitch and was driven home with a Ryan Ludwick sacrifice fly.
"When I hit that ball, I thought it definitely was going to go a long way," Pujols said. "When I was on second, I was talking to Chone Figgins, and he said, 'Man, when you hit that ball, I thought it was going to go a long way, but it didn't.' He made a great catch and pulled it back. Obviously, the ball was on the other side of the wall. But I was happy I got a double out of it. It could have been worse. He could have grabbed that ball and it wouldn't have given Ludwick a chance to drive me in."
Vargas came away with 12 fly-ball outs, seven outs on the ground and four strikeouts. He worked around five hits while giving up one run in 7 2/3 innings, and only David Freese was able to tag him multiple times.
The Cards belted 23 hits and drew eight walks in the previous two games against the Mariners.
"I think he changed speeds well," Ryan said. "He didn't really miss over the middle of the plate, he worked his changeup. I think I saw one cutter/slider pitch. I think it was just two pitches. He worked in and out and I though he located. He just didn't make too many mistakes."
After pinch-hitter Nick Stavinoha doubled to lead off the eighth frame, the Cardinals found their one golden opportunity to tie things up.
With the lineup turning over, La Russa elected to bunt pinch-runner Randy Winn over, but Felipe Lopez wasn't able to drive the runner in as he popped up to second base before Matt Holliday struck out.
"Well I think that is just basic baseball," La Russa said of his decision to bunt. "You are down a run ... we got five or six hits the whole game. What are our chances? We did not have a good game."
With the offense struggling, Garcia proved to be a silver lining. One night after Jeff Suppan turned in a satisfactory first performance, Garcia showed improvement from his last two starts.
The rookie southpaw was more efficient with his pitches, struck out seven for just the second time all season and only walked one. He had walked seven total in his last two games.
"Garcia pitched perfect," Pujols said. "But we didn't give enough run support for him to win the game."